JP6690549B2 - Method for manufacturing printed wiring board - Google Patents

Description

  The present disclosure relates to a photosensitive resin composition, a photosensitive element, a resist pattern forming method, and a printed wiring board manufacturing method.

  In the field of manufacturing printed wiring boards, a photosensitive resin composition is widely used as a resist material used for etching or plating. The photosensitive resin composition includes a support and a photosensitive element (laminated layer), which includes a support and a layer formed on the support using the photosensitive resin composition (hereinafter, also referred to as “photosensitive resin composition layer”). Often used as a body).

  The printed wiring board is manufactured, for example, as follows. First, a photosensitive element having a support and a photosensitive resin composition layer is prepared, and the photosensitive resin composition layer of the photosensitive element is formed on a circuit-forming substrate (photosensitive layer forming step). Next, after peeling and removing the support, an actinic ray is applied to a predetermined portion of the photosensitive resin composition layer to cure the exposed portion (exposure step). Then, by removing (developing) the unexposed portion from the substrate, a resist pattern which is a cured product of the photosensitive resin composition (hereinafter, also referred to as “resist cured product”) is formed on the substrate (development). Process). Next, the substrate on which the resist pattern is formed is subjected to etching treatment or plating treatment to form a circuit on the substrate (circuit forming step), and finally the resist is peeled off to produce a printed wiring board ( Peeling process).

  As an exposure method, a method of exposing a mercury lamp as a light source through a photomask has been conventionally used. Further, in recent years, a direct writing exposure method called DLP (Digital Light Processing) or LDI (Laser Direct Imaging) for directly drawing on a photosensitive resin composition layer based on pattern digital data without using a photomask has been proposed. ing. This direct writing exposure method has better alignment accuracy than the exposure method using a photomask and can obtain a high-definition pattern. Therefore, it is being introduced for producing a high-density package substrate.

  Generally, in the exposure process, it is desired to shorten the exposure time in order to improve production efficiency. However, in the above-described direct drawing exposure method, in addition to using monochromatic light such as a laser as a light source and irradiating an active ray while scanning the substrate, a longer exposure time is required as compared with the conventional exposure method using a photomask. Tends to cost. Therefore, in order to shorten the exposure time and improve the production efficiency, it is necessary to improve the sensitivity of the photosensitive resin composition more than ever before.

  On the other hand, with the recent increase in density of printed wiring boards, there is an increasing demand for a photosensitive resin composition capable of forming a resist pattern having excellent resolution (resolution) and adhesion. In particular, in the production of a package substrate, a photosensitive resin composition capable of forming a resist pattern having an L / S (line width / space width) of 10/10 (unit: μm) or less is desired. Therefore, it is strongly required to improve the resolution and the adhesiveness even in the unit of 1 μm.

  Further, various photosensitive resin compositions have been studied so far. Patent Document 1 discloses a photosensitive resin composition containing a phenolic compound as a polymerization inhibitor. Further, for example, some proposals have been made on photosensitive resin compositions using stable radicals represented by spin trap agents or nitroxyl compounds (see, for example, Patent Documents 2 to 5).

JP, 2000-162767, A JP, 2003-140329, A JP, 2003-215790, A JP 2006-11397 A JP, 2007-133398, A

  However, while the photosensitive resin composition described in Patent Document 1 improves the resolution by containing a polymerization inhibitor, it may delay radical polymerization and may not be able to obtain sufficient sensitivity. . In some cases, the photosensitive resin compositions described in Patent Documents 2 to 5 cannot be said to sufficiently satisfy the sensitivity, resolution, and adhesion for use as a resist for printed wiring board applications. That is, in the conventional photosensitive resin composition, there is still room for improvement in terms of improving resolution and adhesiveness while maintaining sensitivity during resist pattern formation.

  Further, regarding the photosensitive resin composition layer for forming the resist pattern, it is also required to reduce the residue (also referred to as “resist hem” or “tail”) at the bottom of the resist. Residue on the bottom of the resist (resist skirt) is generated when the bottom of the resist spreads due to swelling and does not separate from the substrate even when dried in the developing process. When plating treatment is performed, if the amount of resist skirts generated is large, the contact area between the plating and the substrate becomes small, which causes a decrease in the mechanical strength of the formed circuit. The influence of the resist tail increases as the circuit formation of the printed wiring board becomes finer, and particularly when forming a circuit with L / S of 10/10 (unit: μm) or less, the amount of resist tail generation is large. Therefore, the circuit formation itself after plating may become difficult. Further, in the case of performing the etching treatment, if the amount of resist skirts generated is large, the contact area between the etching solution and the substrate becomes small, so that it becomes difficult to form the conductor pattern as designed. Further, in the case of performing the etching process, if the amount of resist skirts generated is large, the variation in the width of the conductor pattern becomes large, which may affect the yield. Therefore, there is a demand for a photosensitive resin composition capable of forming a resist pattern with a smaller amount of resist tail generation.

  The present disclosure has excellent resolution and adhesiveness, and a photosensitive resin composition capable of forming a resist pattern in which the amount of resist skirt generation is reduced with excellent sensitivity, a photosensitive element using the photosensitive resin composition, An object is to provide a method for forming a resist pattern and a method for manufacturing a printed wiring board.

  As a result of extensive studies to solve the above problems, a binder polymer, a photopolymerizable compound, a 2,4,5-triarylimidazole dimer or a derivative thereof, and a specific nitroxyl compound, in combination, It was found that a photosensitive resin composition capable of forming a resist pattern having excellent resolution and adhesiveness and having a reduced amount of resist skirt generation can be obtained with excellent sensitivity.

  That is, one embodiment of the present disclosure is that (A) component: binder polymer, (B) component: photopolymerizable compound, and (C) component: 2,4,5-triarylimidazole dimer and its derivative. A photopolymerization initiator containing at least one selected from the group consisting of: and a (D) component: a nitroxyl compound, wherein the (D) component is 2,2,6,6-tetramethylpiperidine- Provided is a photosensitive resin composition containing a compound having a 1-oxyl structure.

  The 2,4,5-triarylimidazole dimer and its derivative may contain a compound represented by the following general formula (1).

［式（１）中、Ａｒ^１、Ａｒ^２、Ａｒ^３及びＡｒ^４は、それぞれ独立に、アルキル基、アルケニル基及びアルコキシ基からなる群より選ばれる少なくとも１種の置換基で置換されていてもよいアリール基を示し、Ｘ^１及びＸ^２は、それぞれ独立に、ハロゲン原子、アルキル基、アルケニル基又はアルコキシ基を示し、ｐ及びｑは、それぞれ独立に、１〜５の整数を示す。但し、ｐが２以上の場合、複数存在するＸ^１はそれぞれ同一でも異なっていてもよく、ｑが２以上の場合、複数存在するＸ^２はそれぞれ同一でも異なっていてもよい。］

[In the formula (1), Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may be each independently substituted with at least one substituent selected from the group consisting of an alkyl group, an alkenyl group and an alkoxy group. Represents a good aryl group, X ¹ and X ² each independently represent a halogen atom, an alkyl group, an alkenyl group or an alkoxy group, and p and q each independently represent an integer of 1 to 5. However, when p is 2 or more, a plurality of X ¹ present may be the same or different, and when q is 2 or more, a plurality of X ² may be the same or different. ]

  The component (A) may have a structural unit derived from (meth) acrylic acid and a structural unit derived from a (meth) acrylic acid alkyl ester.

  The photosensitive resin composition according to an embodiment of the present disclosure may further contain (E) component: a phenol compound.

  The photosensitive resin composition according to an embodiment of the present disclosure may further include (F) component: sensitizer, and the (F) component may include a pyrazoline compound.

  Another embodiment of the present disclosure also provides a photosensitive element comprising a support and a photosensitive resin composition layer formed using the photosensitive resin composition provided on the support. To do. By using such a photosensitive element, it is possible to efficiently form a resist pattern having excellent resolution and adhesiveness, and having a reduced amount of generated resist skirt, with excellent sensitivity.

  Another embodiment of the present disclosure is also a photosensitive layer forming step of forming a photosensitive resin composition layer on a substrate by using the photosensitive resin composition or the photosensitive element, and the photosensitive resin composition. An exposure step of irradiating at least a part of a layer with an actinic ray to form a cured product region by photocuring the region, and a region other than the cured product region of the photosensitive resin composition layer on the substrate. And a developing step of forming a resist pattern which is the cured product region on the substrate by removing the resist pattern from above. According to this forming method, it is possible to efficiently form a resist pattern having excellent resolution and adhesion, and having a reduced amount of resist skirt generation, with excellent sensitivity.

  In the above method of forming a resist pattern, the wavelength of the actinic ray to be irradiated may be in the range of 340 nm to 430 nm. This makes it possible to more efficiently form a resist pattern having excellent resolution and adhesiveness and a further reduced amount of resist skirt generation with excellent sensitivity.

  Another embodiment of the present disclosure also provides a method for manufacturing a printed wiring board including a step of etching or plating a substrate having a resist pattern formed by the method of forming a resist pattern. According to this manufacturing method, it is possible to efficiently manufacture a printed wiring board having high-density wiring such as a high-density package substrate with excellent accuracy and productivity.

  According to the present disclosure, a photosensitive resin composition capable of forming a resist pattern having excellent resolution and adhesion, and having a reduced amount of resist skirt generation with excellent sensitivity, and a photosensitive element and a resist pattern using the same And a method for manufacturing a printed wiring board.

It is a schematic cross section which shows one Embodiment of the photosensitive element of this indication. It is a perspective view which shows typically an example of the manufacturing process of the printed wiring board by the semi-additive construction method.

  Hereinafter, modes for carrying out the present disclosure will be described in detail. However, the present disclosure is not limited to the following embodiments. In addition, in this specification, (meth) acrylic acid means acrylic acid or methacrylic acid, and (meth) acrylate means acrylate or methacrylate. The (poly) oxyethylene group means at least one kind of oxyethylene group (sometimes referred to as “EO group”) or polyoxyethylene group in which two or more ethylene groups are linked by an ether bond. The (poly) oxypropylene group means at least one kind of oxypropylene group (sometimes referred to as “PO group”) or polyoxypropylene group in which two or more propylene groups are linked by an ether bond. Further, "EO-modified" means a compound having a (poly) oxyethylene group, "PO-modified" means a compound having a (poly) oxypropylene group, and "EO. “PO-modified” means a compound having both (poly) oxyethylene groups and (poly) oxypropylene groups.

  Further, in the present specification, the term “process” is not limited to an independent process, and even if the process cannot be clearly distinguished from other processes, as long as the intended action of the process is achieved, the term include. Further, the numerical range indicated by using "to" in the present specification indicates a range including the numerical values before and after "to" as the minimum value and the maximum value, respectively. Further, in the numerical ranges described stepwise in the present specification, the upper limit value or the lower limit value of the numerical range of a certain stage may be replaced with the upper limit value or the lower limit value of the numerical range of another stage. Further, in the numerical range described in the present specification, the upper limit value or the lower limit value of the numerical range may be replaced with the value shown in the examples. Further, in the present specification, the term “layer” includes not only the structure of the shape formed over the entire surface but also the structure of a part formed when viewed in a plan view.

  Further, in the present specification, the content of each component in the composition is the sum of the plurality of substances present in the composition, unless a plurality of substances corresponding to each component are present in the composition. Means quantity.

<Photosensitive resin composition>
The photosensitive resin composition according to the present embodiment includes (A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: 2,4,5-triarylimidazole dimer and A photopolymerization initiator containing at least one selected from the group consisting of derivatives, and a (D) component: a nitroxyl compound, wherein the (D) component is 2,2,6,6-tetramethylpiperidine. Includes compounds having a 1-oxyl structure. The photosensitive resin composition may further contain other components, if necessary. In this specification, these components may be simply referred to as the component (A), the component (B), the component (C), the component (D) and the like.

  A binder polymer, a photopolymerizable compound, and a photopolymerization initiator containing at least one selected from the group consisting of 2,4,5-triarylimidazole dimers and derivatives thereof, 2, 2, 6, By using a photosensitive resin composition containing a nitroxyl compound containing a compound having a 6-tetramethylpiperidine-1-oxyl structure, L / S (line width / space width) is 10/10 (unit: μm ) It is possible to form a resist pattern having the following excellent resolution and adhesiveness and a reduced amount of resist skirt generation with excellent sensitivity. Here, excellent adhesion is obtained and the amount of resist skirts generated is reduced by using the above-mentioned photosensitive resin composition, the curing rate at the bottom of the resist pattern is improved, and the swelling of the resist pattern is increased. It is presumed that this is because it is suppressed.

(Component (A): binder polymer)
As the component (A), for example, an acrylic resin, a styrene resin, an epoxy resin, an amide resin, an amide epoxy resin, an alkyd resin, a phenol resin, an ester resin, a urethane resin, or an epoxy resin is obtained by a reaction of (meth) acrylic acid. Examples thereof include an epoxy acrylate resin and an acid-modified epoxy acrylate resin obtained by reacting an epoxy acrylate resin with an acid anhydride. These resins may be used alone or in combination of two or more. From the viewpoint of being more excellent in alkali developability and film formability, it is preferable to use an acrylic resin, and among the acrylic resins, a structural unit derived from (a1) (meth) acrylic acid (hereinafter, also referred to as (a1) component), It is more preferable to use an acrylic resin containing a structural unit derived from (a2) (meth) acrylic acid alkyl ester (hereinafter, also referred to as (a2) component). Here, the “acrylic resin” means a polymer mainly having a monomer unit derived from a polymerizable monomer having a (meth) acryloyl group.

  The acrylic resin, for example, as a polymerizable monomer (monomer), (meth) acrylic acid, (meth) acrylic acid alkyl ester and other polymerizable monomers used as necessary, by a conventional method, Obtained by radical polymerization.

  The content of the structural units derived from (a1) (meth) acrylic acid is, based on the total amount of structural units derived from the polymerizable monomer constituting the binder polymer, from the viewpoint of more effectively exhibiting the developability and the peeling property. It may be 1 to 99% by mass, 5 to 80% by mass, 10 to 60% by mass, or 15 to 50% by mass based on the mass (100% by mass, the same applies hereinafter).

  As the (a2) (meth) acrylic acid alkyl ester, a (meth) acrylic acid alkyl ester having an alkyl group having 1 to 12 carbon atoms is preferable, and an alkyl (meth) acrylic acid having an alkyl group having 1 to 8 carbon atoms is used. Esters are more preferred. Examples of the alkyl (meth) acrylate include methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, butyl (meth) acrylate, pentyl (meth) acrylate, and (meth) acrylate. Hexyl acrylate, heptyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, nonyl (meth) acrylate, decyl (meth) acrylate, undecyl (meth) acrylate, (meth ) Dodecyl acrylate may be mentioned. These may be used alone or in any combination of two or more.

  The content of the structural unit derived from (a2) (meth) acrylic acid alkyl ester is such that, in terms of further excellent releasability, the total mass (100% by mass) of the structural units derived from the polymerizable monomer constituting the binder polymer. May be 1 mass% or more, or 2 mass% or more. Further, in terms of further excellent resolution and adhesion, the content may be 30% by mass or less, 20% by mass or less, or 10% by mass or less.

  The acrylic resin may further contain, as a structural unit, another monomer copolymerizable with the component (a1) and / or the component (a2).

  The other monomer copolymerizable with the above-mentioned component (a1) and / or component (a2) is not particularly limited. Examples of the other monomer include, for example, benzyl (meth) acrylate, cycloalkyl ester of (meth) acrylic acid, benzyl (meth) acrylate derivative, furfuryl (meth) acrylate, tetrahydrofurfuryl (meth) acrylate, ( Isobornyl (meth) acrylate, adamantyl (meth) acrylate, dicyclopentanyl (meth) acrylate, dimethylaminoethyl (meth) acrylate, diethylaminoethyl (meth) acrylate, glycidyl (meth) acrylate, 2,2 , 2-trifluoroethyl (meth) acrylate, 2,2,3,3-tetrafluoropropyl (meth) acrylate, dicyclopentenyloxyethyl (meth) acrylate, dicyclopentanyloxyethyl (meth) acrylate, (Meth) isobornyl acrylate Oxyethyl, cyclohexyloxyethyl (meth) acrylate, adamantyloxyethyl (meth) acrylate, dicyclopentenyloxypropyloxyethyl (meth) acrylate, dicyclopentanyloxypropyloxyethyl (meth) acrylate, (meth) (Meth) acrylic acid esters such as dicyclopentenyloxypropyloxyethyl acrylate and adamantyloxypropyloxyethyl (meth) acrylate; α-bromoacrylic acid, α-chloroacrylic acid, β-furyl (meth) acrylic acid, (Meth) acrylic acid derivatives such as β-styryl (meth) acrylic acid; polymerizable styrene derivatives substituted at the α-position or aromatic ring such as styrene, vinyltoluene, α-methylstyrene; diacetone acrylamide, etc. Acrylic Mido; acrylonitrile; ether compounds of vinyl alcohol such as vinyl-n-butyl ether; maleic acid; maleic anhydride; monoesters of maleic acid such as monomethyl maleate, monoethyl maleate, monoisopropyl maleate; fumaric acid, cinnamic acid , Α-cyanocinnamic acid, itaconic acid, crotonic acid, propiolic acid, and other unsaturated carboxylic acid derivatives; and the like. These may be used alone or in any combination of two or more.

  The acrylic resin may further have a structural unit derived from styrene or a derivative thereof, or a structural unit derived from benzyl (meth) acrylate, from the viewpoint of further reducing the resist skirt. From the viewpoint of improving the resolution, it may further have a structural unit derived from benzyl (meth) acrylate.

  The content of the structural unit derived from benzyl (meth) acrylate in the acrylic resin is based on the total mass of the structural units derived from the polymerizable monomer constituting the binder polymer from the viewpoint of further excellent resolution. As (100% by mass, the same applies below), it may be 3% by mass or more, 5% by mass or more, or 10% by mass or more. Further, from the viewpoint of further excellent releasability and adhesion, the content may be 85% by mass or less, 75% by mass or less, 70% by mass or less, or 50% by mass or less.

  The acid value of the component (A) may be 90 mgKOH / g or more, 100 mgKOH / g or more, 120 mgKOH / g or more, or 130 mgKOH / g or more from the viewpoint of further shortening the development time. From the viewpoint of further improving the adhesiveness of the cured product of the photosensitive resin composition, even if the acid value is 250 mgKOH / g or less, 240 mgKOH / g or less, 235 mgKOH / g or less, or 230 mgKOH / g or less. Good.

The acid value of the component (A) can be measured as follows. That is, first, 1 g of the binder polymer whose acid value is to be measured is precisely weighed. 30 g of acetone is added to the precisely weighed binder polymer, and this is uniformly dissolved. Next, an appropriate amount of phenolphthalein, which is an indicator, is added to the solution, and titration is performed using a 0.1N potassium hydroxide (KOH) aqueous solution. The acid value is determined by calculating the mg number of KOH required to neutralize the acetone solution of the binder polymer to be measured. When a solution obtained by mixing a binder polymer with a synthetic solvent, a diluting solvent or the like is used as a measurement target, the acid value is calculated by the following formula.
Acid value = 0.1 × Vf × 56.1 / (Wp × I / 100)
In the formula, Vf represents the titration amount (mL) of the KOH aqueous solution, Wp represents the measured mass (g) of the solution containing the binder polymer, and I represents the measured non-volatile content in the solution containing the binder polymer. (Mass%) is shown.
When the binder polymer is mixed in a state of being mixed with volatile components such as a synthetic solvent and a diluting solvent, it is heated at a temperature higher than the boiling point of the volatile components by 10 ° C. or more for 1 to 4 hours before being weighed. It is also possible to measure the acid value after removing the components.

  The weight average molecular weight (Mw) of the component (A) is 200,000 or less, 100,000 or less in terms of further excellent developability when measured by gel permeation chromatography (GPC) (converted by a calibration curve using standard polystyrene). , 80,000 or less, or 60,000 or less. The weight average molecular weight may be 10,000 or more, 15,000 or more, 20,000 or more, or 23,000 or more in terms of further excellent adhesion.

  The dispersity (weight average molecular weight / number average molecular weight) of the component (A) may be 3.0 or less, 2.8 or less, or 2.5 or less in terms of further excellent resolution and adhesion.

  The component (A) may have, in the molecule thereof, a characteristic group having photosensitivity to light having a wavelength in the range of 340 nm to 430 nm, if necessary. Examples of the characteristic group include groups formed by removing at least one hydrogen atom from the sensitizer described below.

  The content of the component (A) is 30 parts by mass or more in 100 parts by mass of the total amount of the components (A) and (B) from the viewpoint of further improving the formability of the film (photosensitive resin composition layer). , 35 parts by mass or more, or 40 parts by mass or more. From the viewpoint of further improving sensitivity and resolution, the content may be 70 parts by mass or less, 65 parts by mass or less, or 60 parts by mass or less.

(Component (B): Photopolymerizable compound)
As the component (B), a photopolymerizable compound having an ethylenically unsaturated group can be used.

  Examples of the compound having an ethylenically unsaturated group include a compound having one ethylenically unsaturated group in the molecule, a compound having two ethylenically unsaturated groups in the molecule, and an ethylenically unsaturated group of 3 in the molecule. Compounds having one or more compounds are listed.

  The component (B) preferably contains at least one compound having two ethylenically unsaturated groups in the molecule. When a compound having two ethylenically unsaturated groups is included in the molecule, the content thereof is 5 parts by mass to 70 parts by mass and 5 parts by mass in 100 parts by mass of the total amount of the components (A) and (B). ˜65 parts by mass, or 10 parts by mass to 60 parts by mass.

  Examples of the compound having two ethylenically unsaturated groups in the molecule include bisphenol di (meth) acrylate, hydrogenated bisphenol A-based di (meth) acrylate, di (meth) acrylate having a urethane bond in the molecule, Examples thereof include EO / PO-modified polyalkylene glycol di (meth) acrylate and trimethylolpropane di (meth) acrylate.

  The component (B) is selected from bisphenol type di (meth) acrylate, hydrogenated bisphenol A-based di (meth) acrylate and EO / PO-modified polyalkylene glycol di (meth) acrylate from the viewpoint of further improving the resolution and the peeling property. It is preferable to contain at least one kind of compound having two ethylenically unsaturated groups in the molecule selected from the group consisting of, more preferably at least one kind of bisphenol di (meth) acrylate compound, and to add an EO group. It is more preferable to include at least one of the bisphenol type di (meth) acrylate compounds.

  As the bisphenol type di (meth) acrylate, a compound represented by the following general formula (4) can be used.

In the general formula (4), R ² and R ³ each independently represent a hydrogen atom or a methyl group. XO and YO each independently represent an EO group or a PO group. (XO) _r1 , (XO) _r2 , (YO) _s1 and (YO) _s2 each represent a (poly) oxyethylene group or a (poly) oxypropylene group. r1, r2, s1 and s2 each independently represent 0 to 40. r1, r2, s1 and s2 represent the number of structural units of the structural unit. Therefore, a single molecule shows an integer value, and an aggregate of plural kinds of molecules shows an average rational number. Hereinafter, the same applies to the number of structural units of the structural unit.

  When the compound represented by the general formula (4) has a PO group, the total number of structural units of the PO group in the compound is 2 or more, or 3 or more from the viewpoint of further excellent resist resolution. May be Further, from the viewpoint of further excellent developability, the total number of PO group structural units may be 5 or less.

  When the compound represented by the general formula (4) has an EO group, the total number of structural units of the EO group in the compound is 4 or more, 6 or more, or 8 or more from the viewpoint of further excellent developability. May be Further, from the viewpoint of further excellent resolution, the total number of structural units of the EO group may be 16 or less, or 14 or less.

  Among the compounds represented by the above general formula (4), 2,2-bis (4- (methacryloxide dodecaethoxytetrapropoxy) phenyl) propane is FA-3200MY (Hitachi Chemical Co., Ltd.), 2,2- Bis (4- (methacryloxydiethoxy) phenyl) propane is commercially available as FA-324M (Hitachi Chemical Co., Ltd.) and is 2,2-bis (4- (methacryloxypentaethoxy) phenyl). Propane is commercially available as BPE-500 (Shin-Nakamura Chemical Co., Ltd.) or FA-321M (Hitachi Chemical Co., Ltd.) and is 2,2-bis (4- (methacryloxypentadecaethoxy)). Phenyl) propane is commercially available as BPE-1300 (Shin-Nakamura Chemical Co., Ltd.). These may be used alone or in any combination of two or more.

  When the photosensitive resin composition contains bisphenol type di (meth) acrylate, the content thereof is 1 to 65 parts by mass, 5 to 5 parts by mass per 100 parts by mass of the component (A) and the component (B). It may be 60 parts by mass or 10 to 55 parts by mass.

  Examples of the hydrogenated bisphenol A-based di (meth) acrylate include 2,2-bis (4- (methacryloxypentaethoxy) cyclohexyl) propane. When the photosensitive resin composition contains hydrogenated bisphenol A di (meth) acrylate, the content thereof is 1 to 50 parts by mass in 100 parts by mass of the total amount of the components (A) and (B), Alternatively, it may be 5 to 40 parts by mass.

  In the EO / PO-modified polyalkylene glycol di (meth) acrylate, the (poly) oxyethylene group and the (poly) oxypropylene group in the molecule may exist continuously in a block form, or may exist randomly. May be. In the (poly) oxyisopropylene group, the secondary carbon of the isopropylene group may be bonded to the oxygen atom, or the primary carbon may be bonded to the oxygen atom.

  Examples of commercially available EO / PO-modified polyalkylene glycol di (meth) acrylates include polyalkylene glycol di (meth) having EO groups: 6 (average value) and PO groups: 12 (average value). ) Acrylate (Hitachi Chemical Co., Ltd., “FA-023M”), polyalkylene glycol di (meth) acrylate having EO group: 6 (average value) and PO group: 12 (average value) (Hitachi Chemical Co., Ltd., “FA-024M”) and the like.

  When the above-mentioned photosensitive resin composition contains EO / PO-modified polyalkylene glycol di (meth) acrylate, the content of the component (A) and the component (B) is 100 parts by mass in terms of resolution. From the viewpoint of improvement, it may be 5 to 30 parts by mass, or 10 to 20 parts by mass.

  The component (B) may include at least one photopolymerizable compound having three or more ethylenically unsaturated groups in the molecule.

  Examples of the compound having three or more ethylenically unsaturated groups include trimethylolpropane tri (meth) acrylate and EO-modified trimethylolpropane tri (meth) acrylate (having 1 to 5 oxyethylene group structural units). , PO-modified trimethylolpropane tri (meth) acrylate, EO / PO-modified trimethylolpropane tri (meth) acrylate, tetramethylolmethane tri (meth) acrylate and tetramethylolmethane tetra (meth) acrylate, pentaerythritol tri (meth) acrylate , EO-modified pentaerythritol tetraacrylate or dipentaerythritol hexa (meth) acrylate. These can be used alone or in combination of two or more.

  Tetramethylolmethane triacrylate is A-TMM-3 (Shin-Nakamura Chemical Co., Ltd.), EO-modified trimethylolpropane trimethacrylate is TMPT21E and TMPT30E (Hitachi Chemical Co., Ltd.), and pentaerythritol triacrylate is As SR444 (Sartomer Co., Ltd.), dipentaerythritol hexaacrylate is A-DPH (Shin-Nakamura Chemical Co., Ltd.), EO-modified pentaerythritol tetraacrylate is ATM-35E (Shin-Nakamura Chemical Co., Ltd.) Is commercially available as.

  When the photopolymerizable compound having three or more ethylenically unsaturated groups in the molecule is contained, the content thereof is well balanced in resolution, adhesion, resist shape and peeling property after curing, and from the viewpoint of further improving ( It may be 3 to 30 parts by mass, 5 to 25 parts by mass, or 5 to 20 parts by mass in 100 parts by mass of the total amount of the components A) and (B).

  The component (B) has one ethylenically unsaturated group in the molecule from the viewpoint of further improving the resolution, adhesiveness, resist shape and peeling property after curing in a well-balanced manner, or from the viewpoint of further suppressing scum generation. You may include the photopolymerizable compound which has.

  Examples of the photopolymerizable compound having one ethylenically unsaturated group in the molecule include nonylphenoxypolyoxyethylene acrylate, a phthalic acid compound, and a (meth) acrylic acid alkyl ester. Among the above, nonylphenoxypolyoxyethylene acrylate or a phthalic acid compound is preferably contained from the viewpoint of further improving the balance, the resolution, the adhesiveness, the resist shape and the peeling property after curing.

  When the photopolymerizable compound having one ethylenically unsaturated group in the molecule is contained, the content thereof is 1 to 20 parts by mass, 3 to 3 parts by mass per 100 parts by mass of the components (A) and (B). It may be 15 parts by mass or 5 to 12 parts by mass.

  The total content of the component (B) in the photosensitive resin composition is 30 to 70 parts by mass, 35 to 65 parts by mass, or 35 with respect to 100 parts by mass of the total amount of the components (A) and (B). It may be up to 60 parts by mass. When the content is 30 parts by mass or more, the sensitivity and resolution tend to be further improved. When the content is 70 parts by mass or less, a film (photosensitive resin composition layer) tends to be easily formed, and a good resist shape tends to be easily obtained.

(Component (C): photopolymerization initiator)
The photosensitive composition contains, as the component (C), a photopolymerization initiator containing at least one selected from the group consisting of 2,4,5-triarylimidazole dimers and their derivatives. The 2,4,5-triarylimidazole dimer and the derivative thereof further improve the sensitivity and the adhesiveness, and further reduce the amount of generated resist skirts, and thus the compound represented by the general formula (1). May be included.

In general formula (1), at least one of X ¹ and X ² is preferably a chlorine atom. When Ar ¹ , Ar ² , Ar ³ and Ar ⁴ are each independently an aryl group having at least one substituent selected from the group consisting of an alkyl group, an alkenyl group and an alkoxy group, the number of the above substituents is It is preferably 1 to 5, more preferably 1 to 3, and even more preferably 1. When Ar ¹ , Ar ² , Ar ³ and Ar ⁴ are each independently an aryl group having the above-mentioned substituent, the substitution position is not particularly limited and is preferably the ortho position or the para position. p and q are each independently an integer of 1 to 5, more preferably an integer of 1 to 3, and even more preferably 1.

  Examples of the compound represented by the general formula (1) include 2- (o-chlorophenyl) -4,5-diphenylimidazole dimer, 2- (o-chlorophenyl) -4,5-di (methoxyphenyl). Imidazole dimer, 2- (o-fluorophenyl) -4,5-diphenylimidazole dimer, 2- (o-methoxyphenyl) -4,5-diphenylimidazole dimer, 2- (p-methoxyphenyl) ) -4,5-Diphenylimidazole dimer. In addition, the substituents of the aryl groups of the two 2,4,5-triarylimidazoles may be the same and may give a target compound, or may be different and give an asymmetric compound. These are used individually by 1 type or in combination of 2 or more types.

  As the component (C), in addition to the 2,4,5-triarylimidazole dimer or the derivative thereof, other commonly used photopolymerization initiator may be contained. Other photopolymerization initiators include, for example, benzophenone, N, N, N ', N'-tetramethyl-4,4'-diaminobenzophenone (Michler's ketone), N, N, N', N'-tetraethyl-4. , 4'-diaminobenzophenone, 4-methoxy-4'-dimethylaminobenzophenone, 2-benzyl-2-dimethylamino-1- (4-morpholinophenyl) -butanone-1,2-methyl-1- [4- (Methylthio) phenyl] -2-morpholino-propanone-1 and other aromatic ketones, 2-ethylanthraquinone, phenanthrenequinone, 2-tert-butylanthraquinone, octamethylanthraquinone, 1,2-benzanthraquinone, 2,3-benz Anthraquinone, 2-phenylanthraquinone, 2,3-diphenylanthraquine And quinones such as 1-chloroanthraquinone, 2-methylanthraquinone, 1,4-naphthoquinone, 9,10-phenanthraquinone, 2-methyl-1,4-naphthoquinone and 2,3-dimethylanthraquinone, benzoinmethyl Benzoin ether compounds such as ether, benzoin ethyl ether, benzoin phenyl ether, benzoin compounds such as benzoin, methylbenzoin, ethylbenzoin, 1,2-octanedione-1- [4- (phenylthio) phenyl] -2- (O- Benzoyl oxime), 1- [9-ethyl-6- (2-methylbenzoyl) -9H-carbazol-3-yl] ethanone 1- (O-acetyloxime) and other oxime ester compounds, benzyl dimethyl ketal and other benzyl derivatives , 9-phenylacridine 1,7-bis (9,9'-acridinyl) acridine derivatives such as heptane, N- phenylglycine, etc. N- phenylglycine derivatives.

  The content of the component (C) is 0.1 to 10 parts by mass, 1 to 7 parts by mass, 2 to 6 parts by mass, or 3 to 3 parts by mass based on 100 parts by mass of the total amount of the components (A) and (B). It may be 5 parts by mass. When the content of the component (C) is 0.1 parts by mass or more, better sensitivity, resolution, or adhesiveness is easily obtained, and the amount of resist skirts generated tends to be further reduced. It tends to be easier to obtain a better resist shape.

(Component (D): nitroxyl compound)
The nitroxyl compound means a compound having a nitroxyl group. It can be said that the nitroxyl group is a group represented by the following structural formula (5).

  The component (D) contains a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure as a nitroxyl compound. By using the compound having the above structure in combination with at least one member selected from the group consisting of 2,4,5-triarylimidazole dimers and derivatives thereof, excellent resolution and adhesion, and resist skirt generation It is possible to obtain a photosensitive resin composition capable of forming a resist pattern having a reduced amount with excellent sensitivity.

  The compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure may be a compound represented by the following general formula (2). By containing the compound represented by the following general formula (2) in the photosensitive resin composition, it is possible to further improve the resolution and adhesion of the resist pattern to be formed while having good sensitivity and resist. The amount of skirt generation can be further reduced.

［式（２）中、Ｒ^１はヒドロキシル基、炭素数１〜５のアルキル基、アセトアミド基、アミノ基、クロロアセトアミド基、シアノ基、ベンゾイルオキシ基又は下記一般式（３）で示される基を示す。］

[In the formula (2), R ¹ represents a hydroxyl group, an alkyl group having 1 to 5 carbon atoms, an acetamido group, an amino group, a chloroacetamido group, a cyano group, a benzoyloxy group or a group represented by the following general formula (3). Show. ]

［式（３）中、ｎ１は１〜１２の整数を示す。］

[In Formula (3), n1 shows the integer of 1-12. ]

  In addition, in the photosensitive resin composition, the compound represented by the general formula (2) may exist in a state in which the free radical site is bonded to another compound or an organic group.

In general formula (2), R ¹ is preferably a hydroxyl group, an acetamide group, or a benzoyloxy group. When R ¹ is a hydroxyl group, the amount of resist tail generated can be further reduced. When R ¹ is an acetamide group or a benzoyloxy group, the sensitivity can be further improved.

  Examples of the compound represented by the general formula (2) include 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-hydroxy-2,2,6,6-tetra Methylpiperidine-1-oxylbenzoate free radical, 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-amino-2,2,6,6-tetramethylpiperidine-1- Oxyl free radical, 4- (2-chloroacetamide) -2,2,6,6-tetramethylpiperidine-1-oxyl free radical, 4-cyano-2,2,6,6-tetramethylpiperidine-1-oxyl Free radicals and 4-methoxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radicals are mentioned.These may be used alone or in any combination of two or more.

  Examples of other compounds having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure include 2,2,6,6-tetramethylpiperidine-1-oxyl free radical. This compound can be used in combination with the compound represented by the general formula (2), but it is difficult to use it alone because of its high volatility.

  The component (D) may contain a nitroxyl compound other than the compound having the 2,2,6,6-tetramethylpiperidine-1-oxyl structure.

  The content of the component (D) may be 0.005 to 10 parts by mass, 0.01 to 8 parts by mass, or 0.01 to 5 parts by mass with respect to 100 parts by mass of the total amount of the component (A). Good. When the content is 0.005 parts by mass or more, the resolution and adhesion tend to be more excellent, and when it is 10 parts by mass or less, the sensitivity tends to be more excellent. The content of the component (D) is 0.005 to 20 parts by mass, 0.01 to 5 parts by mass, or 0.02-1 to 100 parts by mass of the total amount of the components (A) and (B). It may be part by mass. When the content is 0.005 parts by mass or more, the resolution and the suppression of the amount of generated resist skirts tend to be more excellent, and when the content is 20 parts by mass or less, the sensitivity tends to be more excellent.

(Component (E): phenolic compound)
It is more preferable that the photosensitive resin composition contains at least one phenolic compound in combination with the components (A) to (D), from the viewpoint of further improving the resolution. Examples of the component (E) include 2,2-methylene-bis (4-methyl-6-tert-butylphenol), catechol, picric acid, 4-tert-butylcatechol, 2,6-ditertiarybutyl-p. -Cresol, 4,4'-thiobis [ethylene (oxy) (carbonyl) (ethylene)] bis [2,6-bis (1,1-dimethylethyl) phenol] and the like can be mentioned.

  The content of the component (E) is 0.0001 to 1 part by mass, 0.001 to 0.1 part by mass, or 0.005 to 0.01 part by mass based on 100 parts by mass of the total amount of the component (A). It may be a department. When this content is 0.0001 parts by mass or more, the resolution and adhesion tend to be more excellent, and when it is 1 part by mass or less, the sensitivity tends to be more excellent.

  A photosensitive resin composition according to an embodiment of the present disclosure contains a component (F): a sensitizer and / or a component (G): a hydrogen donor, in addition to the components (A) to (E) described above. It is preferable.

(Component (F): sensitizer)
The photosensitive resin composition preferably contains at least one sensitizer. The sensitizer can effectively use the absorption wavelength of the actinic ray used for exposure, and a compound having a maximum absorption wavelength of 340 nm to 420 nm is preferable.

  Examples of the component (F) include pyrazoline compounds, anthracene compounds, acridone compounds, coumarin compounds, xanthone compounds, oxazole compounds, benzoxazole compounds, thiazole compounds, benzothiazole compounds, triazole compounds, stilbene compounds, triazine compounds, thiophene compounds, Examples thereof include naphthalimide compounds. In particular, the component (F) preferably contains a pyrazoline compound or an anthracene compound, more preferably a pyrazoline compound, from the viewpoint of further improving the resolution, adhesion and sensitivity. The sensitizer as the component (F) may be used alone or in combination of two or more.

The pyrazoline compound may be a compound represented by the following general formula (6) from the viewpoint of improving the balance of sensitivity and resolution.

  In general formula (6), R represents an alkoxy group having 1 to 10 carbon atoms or an alkyl group having 1 to 12 carbon atoms, a, b and c each independently represent an integer of 0 to 5, a, b and The sum of c is 1 to 6. When the sum of a, b and c is 2 to 6, a plurality of Rs in the same molecule may be the same or different.

  The R may be linear or branched. Examples of R include, but are not limited to, a methoxy group, an isopropyl group, an n-butyl group, a tert-butyl group, a tert-octyl group, and a dodecyl group. Further, the total sum of a, b and c in the general formula (6) is 1 to 6, more preferably 1 to 4, and particularly preferably 1 or 2.

  From the viewpoint of further improving sensitivity and solubility, the compound represented by the general formula (6) is a pyrazoline compound in which R is an alkoxy group having 1 to 10 carbon atoms or an alkyl group having 1 to 3 carbon atoms. preferable. Among them, 1-phenyl-3- (4-methoxystyryl) -5- (4-methoxyphenyl) pyrazoline is particularly preferable from the viewpoint of improving easiness of synthesis and sensitivity, and easiness of synthesis and dissolution in a solvent. From the viewpoint of improving the properties, 1-phenyl-3- (4-isopropylstyryl) -5- (4-isopropylphenyl) pyrazoline is particularly preferable.

  Since the photosensitive resin composition contains a pyrazoline compound as the component (F), 2,4,5-triarylimidazole dimer or its derivative and 2,2,6,6-tetramethylpiperidine-1-oxyl The effect of improving the sensitivity, the resolution and the adhesion by the combination with the compound having the structure, and the effect of reducing the amount of resist skirt generation can be further enhanced. That is, a combination of three components of a 2,4,5-triarylimidazole dimer or a derivative thereof, a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure, and a pyrazoline compound, It is possible to obtain extremely good sensitivity, resolution and adhesion, and it is possible to significantly reduce the amount of resist skirt generation.

  When the photosensitive resin composition contains the component (F), its content is 0.01 to 10 parts by mass, and 0.05 to 100 parts by mass based on 100 parts by mass of the total amount of the components (A) and (B). It may be 5 parts by mass or 0.1 to 3 parts by mass. When the content is 0.01 parts by mass or more, the sensitivity and resolution are more excellent, and the amount of generated resist skirts tends to be further reduced. When the content is 10 parts by mass or less, a better resist shape is obtained. Tends to be easily damaged.

((G) component: hydrogen donor)
The photosensitive resin composition may contain at least one hydrogen donor from the viewpoint of improving the contrast between the exposed portion and the unexposed portion (also referred to as “imaging property”). The hydrogen donor is not particularly limited as long as it can provide hydrogen to the photopolymerization initiator during the reaction in the exposed area, and examples thereof include bis [4- (dimethylamino) phenyl] methane and bis [4- (Diethylamino) phenyl] methane, leuco crystal violet and the like. These can be used alone or in combination of two or more.

  When the component (G) is included, its content is 0.01 to 10 parts by mass, 0.05 to 5 parts by mass, or 0 with respect to 100 parts by mass of the total amount of the components (A) and (B). 1 to 2 parts by mass may be used. If the content is 0.01 parts by mass or more, it tends to be easier to obtain better sensitivity. When the content is 10 parts by mass or less, precipitation of an excessive (G) component as a foreign substance tends to be suppressed after the film is formed.

(Other ingredients)
The photosensitive resin composition of the present embodiment is, if necessary, a photopolymerizable compound (oxetane compound or the like) having at least one cationically polymerizable cyclic ether group in the molecule, a cationic polymerization initiator, malachite green, Victoria. Dyes such as pure blue, brilliant green and methyl violet, photo-coloring agents such as tribromophenyl sulfone, diphenylamine, benzylamine, triphenylamine, diethylaniline and 2-chloroaniline, thermal color inhibitors, 4-toluenesulfonamide, etc. Plasticizers, pigments, fillers, defoamers, flame retardants, stabilizers, adhesion promoters, leveling agents, peeling accelerators, antioxidants, fragrances, imaging agents, thermal crosslinking agents, etc. . These are used alone or in combination of two or more. When the photosensitive resin composition contains other components, the content of each of them is about 0.01 to 20 parts by mass with respect to 100 parts by mass of the total amount of the components (A) and (B). preferable.

[Solution of photosensitive resin composition]
The photosensitive resin composition of the present embodiment may further contain at least one organic solvent in order to adjust the viscosity, if necessary. Examples of the organic solvent include alcohol solvents such as methanol and ethanol; ketone solvents such as acetone and methyl ethyl ketone; glycol ether solvents such as methyl cellosolve, ethyl cellosolve and propylene glycol monomethyl ether; aromatic hydrocarbon solvents such as toluene; N, N- Examples include aprotic polar solvents such as dimethylformamide. These may be used alone or in combination of two or more. The content of the organic solvent contained in the photosensitive resin composition can be appropriately selected according to the purpose and the like. For example, the photosensitive resin composition can be used as a solution having a solid content of about 30 to 60% by mass. Hereinafter, the photosensitive resin composition containing an organic solvent is also referred to as a "coating liquid".

  The photosensitive resin composition can be used to form a photosensitive resin composition layer by applying (for example, coating) the surface of a support, a metal plate, or the like, which will be described later, with the coating liquid and drying the coating liquid. . The metal plate is not particularly limited and can be appropriately selected depending on the purpose and the like. Examples of the metal plate include metal plates such as copper, copper-containing alloys, iron-containing alloys such as nickel, chromium, iron, and stainless steel. The metal plate is preferably a metal plate made of copper, a copper-containing alloy, an iron-containing alloy, or the like.

  The thickness of the formed photosensitive resin composition layer is not particularly limited and can be appropriately selected depending on the application. The thickness of the photosensitive resin composition layer may be, for example, 1 to 100 μm after drying. When the photosensitive resin composition layer is formed on the metal plate, the surface of the photosensitive resin composition layer opposite to the metal plate may be covered with a protective layer. Examples of the protective layer include polymer films such as polyethylene and polypropylene.

  The photosensitive resin composition can be applied to the formation of the photosensitive resin composition layer of the photosensitive element described below. That is, another embodiment of the present disclosure is that (A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: 2,4,5-triarylimidazole dimer, and A photopolymerization initiator containing at least one selected from the group consisting of its derivatives, and a (D) component: a nitroxyl compound, wherein the (D) component is 2,2,6,6-tetramethylpiperidine. It is an application of a photosensitive resin composition containing a compound having a -1-oxyl structure to a photosensitive element.

  Further, the photosensitive resin composition of the present embodiment can be used in the method for forming a resist pattern described later. That is, another embodiment of the present disclosure is that (A) component: binder polymer, (B) component: photopolymerizable compound, (C) component: 2,4,5-triarylimidazole dimer, and A photopolymerization initiator containing at least one selected from the group consisting of its derivatives, and a (D) component: a nitroxyl compound, wherein the (D) component is 2,2,6,6-tetramethylpiperidine. It is an application of a photosensitive resin composition containing a compound having a -1-oxyl structure to a method for forming a resist pattern.

<Photosensitive element>
A photosensitive element according to an embodiment of the present disclosure includes a support and a photosensitive resin composition layer formed on the support and formed of the photosensitive resin composition. The photosensitive resin composition layer may be a coating film. The coating film as used in this specification is a coating film in which the photosensitive resin composition is in an uncured state. The photosensitive element may have other layers such as a protective layer if necessary.

  FIG. 1 shows one embodiment of the photosensitive element. In the photosensitive element 1 shown in FIG. 1, a support 2, a photosensitive resin composition layer 3 formed of a photosensitive resin composition, and a protective layer 4 are laminated in this order. The photosensitive element 1 can be obtained as follows, for example. A coating liquid (that is, a photosensitive resin composition containing an organic solvent) is applied onto the support 2 to form a coating layer, and the coating layer is dried to form the photosensitive resin composition layer 3. Then, the surface of the photosensitive resin composition layer 3 opposite to the support 2 is covered with a protective layer 4 to form the support 2 and the photosensitive resin composition layer 3 formed on the support 2. And the protective layer 4 laminated on the photosensitive resin composition layer 3, the photosensitive element 1 of the present embodiment is obtained. The photosensitive element 1 does not necessarily have to include the protective layer 4.

  As the support, a polymer film made of a polymer having heat resistance and solvent resistance such as polyester such as polyethylene terephthalate, polyolefin such as polypropylene and polyethylene, can be used.

  The thickness of the support (polymer film) may be 1 to 100 μm, 5 to 50 μm, and 5 to 30 μm. When the thickness of the support is 1 μm or more, it is possible to prevent the support from breaking when the support is peeled off. Further, when the thickness is 100 μm or less, deterioration of resolution is suppressed.

  The protective layer preferably has a smaller adhesive force to the photosensitive resin composition layer than the adhesive force to the photosensitive resin composition layer of the support. Also, a low fish eye film is preferred. The term "fish eye" used herein means that when a material is heat-melted, kneaded, extruded, biaxially stretched, or produced by a casting method, foreign matter, undissolved material, oxidative deterioration material or the like in the film Means something that has been taken into. That is, the "low fish eye" means that there are few foreign substances in the film.

  Specifically, as the protective layer, a polymer film made of a polymer having heat resistance and solvent resistance such as polyester such as polyethylene terephthalate, polyolefin such as polypropylene and polyethylene can be used. Examples of commercially available products include polypropylene films such as Alfan MA-410 and E-200 manufactured by Oji Paper Co., Ltd., Shin-Etsu Film Co., Ltd., and PS series polyethylene terephthalate films such as PS-25 manufactured by Teijin Ltd. To be The protective layer 4 may be the same as the support 2.

  The thickness of the protective layer may be 1-100 μm, 5-50 μm, 5-30 μm, or 15-30 μm. When the thickness of the protective layer is 1 μm or more, it is possible to prevent the protective layer from being broken when the photosensitive resin composition layer and the support are laminated on the substrate while peeling off the protective layer. When the thickness of the protective layer is 100 μm or less, the handleability and the cost are excellent.

  Specifically, the photosensitive element of this embodiment can be manufactured as follows, for example. Component (A): Binder polymer, Component (B): Photopolymerizable compound, Component (C): At least one selected from the group consisting of 2,4,5-triarylimidazole dimer and its derivative. And a nitroxyl compound containing a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure (D) component are dissolved in an organic solvent to prepare a coating liquid. A manufacturing method comprising: a step, a step of applying (for example, coating) the coating liquid on a support to form a coating layer, and a step of drying the coating layer to form a photosensitive resin composition layer. Can be manufactured in.

  The coating of the solution of the photosensitive resin composition on the support can be carried out by a known method such as roll coating, comma coating, gravure coating, air knife coating, die coating or bar coating.

  Drying of the coating layer is not particularly limited as long as at least a part of the organic solvent can be removed from the coating layer, and for example, it can be dried at 70 to 150 ° C. for 5 to 30 minutes. After drying, the amount of the residual organic solvent in the photosensitive resin composition layer may be 2% by mass or less from the viewpoint of preventing the diffusion of the organic solvent in a subsequent step.

  The thickness of the photosensitive resin composition layer in the photosensitive element can be appropriately selected depending on the application. The thickness of the photosensitive resin composition layer may be 1 to 100 μm, 1 to 50 μm, or 5 to 40 μm after drying. When the thickness of the photosensitive resin composition layer is 1 μm or more, industrial coating becomes easy. When it is 100 μm or less, the adhesion and resolution tend to be more excellent.

  The transmittance of the photosensitive resin composition layer with respect to ultraviolet rays may be 5 to 75%, 10 to 65%, or 15 to 55% with respect to ultraviolet rays having a wavelength range of 350 nm to 420 nm. If this transmittance is 5% or more, it tends to be easier to obtain better adhesion. If it is 75% or less, a better resolution tends to be easily obtained. The transmittance can be measured with a UV spectrometer. Examples of the UV spectrometer include a 228A W-beam spectrophotometer manufactured by Hitachi, Ltd.

  The photosensitive element may further have an intermediate layer such as a cushion layer, an adhesive layer, a light absorbing layer and a gas barrier layer. As these intermediate layers, for example, the intermediate layer described in JP-A-2006-098982 can also be applied in one embodiment of the present disclosure.

  The photosensitive element of the present embodiment can be suitably used, for example, in a method of forming a resist pattern described later.

<Method of forming resist pattern>
A resist pattern can be formed using the photosensitive resin composition or the photosensitive element. The method for forming a resist pattern of the present embodiment includes (i) a step of forming a photosensitive resin composition layer on the substrate using the photosensitive resin composition or the photosensitive element (photosensitive layer forming step), (Ii) a step of irradiating at least a part of the region of the photosensitive resin composition layer with an actinic ray to photocure the region to form a cured product region (exposure step); and (iii) the photosensitivity A step (developing step) of removing a region of the resin composition layer other than the cured product region from the substrate to form a resist pattern which is the cured product region on the substrate. The method for forming a resist pattern may further include other steps as necessary, and the photosensitive resin composition layer in the photosensitive layer forming step may be a coating film. The photosensitive resin composition and the photosensitive element can also be applied to a method for producing a substrate with a resist pattern, which obtains a substrate with a resist pattern by the method for forming the resist pattern.

(I) Photosensitive layer forming step First, a photosensitive resin composition layer is formed on a substrate using the above-mentioned photosensitive resin composition or the above-mentioned photosensitive element. As the substrate, a substrate (circuit forming substrate) including an insulating layer and a conductor layer formed on the insulating layer can be used.

  The photosensitive resin composition layer is formed on the substrate by, for example, in the case where the photosensitive element has the protective layer 4, after removing the protective layer, the photosensitive resin composition layer of the photosensitive element is formed. Is heated and pressure-bonded to the substrate. When the photosensitive resin composition is used, the photosensitive resin composition layer can be formed by applying (for example, coating) the coating solution on the surface of the substrate and drying the coating solution. Thereby, a laminate in which the substrate, the photosensitive resin composition layer and the support are laminated in this order is obtained.

This photosensitive layer forming step is preferably performed under reduced pressure from the viewpoint of adhesion and followability. Heating to at least one of the photosensitive resin composition layer and the substrate during pressure bonding is preferably performed at a temperature of 70 to 130 ° C., and a pressure of about 0.1 to 1.0 MPa (about 1 to 10 kgf / cm ² ). It is preferable to crimp. These conditions are not particularly limited and may be appropriately selected as needed. If the photosensitive resin composition layer is heated to 70 to 130 ° C., it is not necessary to preheat the substrate in advance. Pre-heat treatment of the circuit-forming substrate can further improve the adhesion and the followability.

(Ii) Exposure Step In the exposure step, the exposed portion irradiated with the actinic ray is exposed by irradiating the actinic ray to at least a part of the region of the photosensitive resin composition layer formed on the substrate as described above. Light-cured to form a latent image. At this time, when a support is present on the photosensitive resin composition layer, if the support is transparent to the actinic rays, the actinic rays can be irradiated through the support. On the other hand, when the support has a property of shielding actinic rays from light, the photosensitive resin composition layer is irradiated with actinic rays after the support is removed.

  Examples of the exposure method include a method (mask exposure method) in which an actinic ray is imagewise irradiated through a negative or positive mask pattern called an artwork. Moreover, you may employ | adopt the method of irradiating an actinic ray imagewise by the direct drawing exposure methods, such as a LDI (Laser Direct Imaging) exposure method or a DLP (Digital Light Processing) exposure method.

  The light source of the actinic ray is not particularly limited, and a known light source can be used. For example, carbon arc lamps, mercury vapor arc lamps, high-pressure mercury lamps, xenon lamps, gas lasers such as argon lasers, solid-state lasers such as YAG lasers, semiconductor lasers, ultraviolet rays such as blue-violet lasers such as gallium nitride, visible light, etc. The one that emits is used.

  The wavelength of the actinic ray (exposure wavelength) is preferably in the range of 340 to 430 nm, more preferably in the range of 350 to 420 nm, from the viewpoint of more reliably obtaining the effect of the embodiment of the present disclosure. preferable.

(Iii) Developing Step In the developing step, the uncured portion of the photosensitive resin composition layer is removed from the circuit-forming substrate by a developing treatment, so that the photosensitive resin composition layer is a photocured cured resist. A pattern is formed on the substrate. When the support is present on the photosensitive resin composition layer, the support is removed and then the unexposed portion is removed (developed). The development processing includes wet development and dry development, but wet development is widely used.

  In the case of wet development, it is developed by a known developing method using a developing solution corresponding to the photosensitive resin composition. Examples of the developing method include a method using a dip method, a paddle method, a spray method, brushing, slapping, scrubbing, rocking dipping and the like, and a high pressure spray method is preferable from the viewpoint of improving resolution. You may develop by combining these 2 or more types of methods.

  The developing solution is appropriately selected according to the constitution of the photosensitive resin composition. Examples of the developing solution include alkaline aqueous solutions and organic solvent developing solutions.

  When used as a developing solution, an alkaline aqueous solution is safe and stable, and has good operability. Examples of the base of the alkaline aqueous solution include alkali hydroxide such as lithium, sodium or potassium hydroxide; alkali carbonate such as lithium, sodium, potassium or ammonium carbonate or bicarbonate; potassium phosphate, sodium phosphate and the like. Alkali metal phosphates: alkali metal pyrophosphates such as sodium pyrophosphate, potassium pyrophosphate, etc., borax (sodium tetraborate), sodium metasilicate, tetramethylammonium hydroxide, ethanolamine, ethylenediamine, diethylenetriamine, 2 -Amino-2-hydroxymethyl-1,3-propanediol, 1,3-diamino-2-propanol, morpholine and the like are used.

  As the alkaline aqueous solution used for the development, a dilute solution of 0.1 to 5 mass% sodium carbonate, a dilute solution of 0.1 to 5 mass% potassium carbonate, a dilute solution of 0.1 to 5 mass% sodium hydroxide, and 0.1. A dilute solution of 1 to 5 mass% sodium tetraborate or the like is preferable. The pH of the alkaline aqueous solution is preferably in the range of 9-11. The temperature is adjusted according to the alkali developability of the photosensitive resin composition layer. A surface active agent, a defoaming agent, and a small amount of an organic solvent for accelerating development may be mixed in the alkaline aqueous solution.

  The alkaline aqueous solution may contain one or more organic solvents. Examples of the organic solvent used include acetone, ethyl acetate, alkoxyethanol having an alkoxy group having 1 to 4 carbon atoms, ethyl alcohol, isopropyl alcohol, butyl alcohol, diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether and the like. . These are used alone or in combination of two or more. When the organic solvent is contained, the content of the organic solvent is preferably 2 to 90% by mass based on the total mass of the alkaline aqueous solution (100% by mass). The temperature can be adjusted according to the alkali developing property. The alkaline aqueous solution used for development may contain a small amount of a surfactant, a defoaming agent, or the like.

  Examples of the organic solvent used for the organic solvent developer include 1,1,1-trichloroethane, N-methylpyrrolidone, N, N-dimethylformamide, cyclohexanone, methyl isobutyl ketone, and γ-butyrolactone. In order to prevent ignition, it is preferable to add water in the range of 1 to 20 mass% to these organic solvents to prepare an organic solvent developer.

In the method of forming a resist pattern, after removing the unexposed portion, the resist pattern is further cured by heating at 60 to 250 ° C. or exposing at an energy amount of 0.2 to 10 J / cm ² if necessary. It may further include the step of

<Method of manufacturing printed wiring board>
A method for manufacturing a printed wiring board according to an embodiment of the present disclosure includes forming a resist pattern on a conductor layer of a substrate (circuit forming substrate) including an insulating layer and a conductor layer formed on the insulating layer. The method includes a step of forming a conductor pattern (also referred to as a “circuit pattern”) by etching or plating a substrate on which a resist pattern is formed by the method. The method for manufacturing a printed wiring board may include other steps such as a resist removing step, if necessary. The etching process or the plating process on the substrate is performed on the conductor layer or the like of the substrate using the formed resist pattern as a mask.

  In the etching process, the conductor pattern of the circuit forming substrate which is not covered with the cured resist is removed by etching using the resist pattern (cured resist) formed on the substrate as a mask to form a conductor pattern. The etching method is appropriately selected according to the conductor layer to be removed. Examples of the etching solution include cupric chloride aqueous solution, ferric chloride aqueous solution, alkali etching solution, hydrogen peroxide etching solution, and the like. Of these, an aqueous ferric chloride solution may be used because it has a good etch factor.

  On the other hand, in the plating process, using a resist pattern (cured resist) formed on the substrate as a mask, copper, solder or the like is plated on the conductor layer of the circuit forming substrate which is not covered with the cured resist. After the plating process, the cured resist is removed, and the conductor layer covered with the cured resist is etched to form a conductor pattern. The method of plating treatment may be electrolytic plating treatment or electroless plating treatment. The plating treatment includes copper sulfate plating, copper plating such as copper pyrophosphate plating, solder plating such as high-throw solder plating, Watts bath (nickel sulfate-nickel chloride) plating, nickel plating such as nickel sulfamate, hard gold plating, soft plating. Examples thereof include gold plating such as gold plating.

  After the etching process and the plating process, the resist pattern on the substrate is removed (peeled). The removal of the resist pattern can be performed using, for example, an aqueous solution having a stronger alkaline property than the alkaline solution used in the developing step. As this strongly alkaline aqueous solution, 1 to 10 mass% sodium hydroxide aqueous solution, 1 to 10 mass% potassium hydroxide aqueous solution, etc. are used. Above all, it is preferable to use a 1 to 10 mass% sodium hydroxide aqueous solution or a 1 to 10 mass% potassium hydroxide aqueous solution, and it is more preferable to use a 1 to 5 mass% sodium hydroxide aqueous solution or a 1 to 5 mass% potassium hydroxide aqueous solution. preferable. Examples of the method of applying the strongly alkaline aqueous solution to the resist pattern include a dipping method and a spray method. These may be used alone or in combination of two or more.

  When the resist pattern is removed after performing the plating process, the conductor layer covered with the cured resist is removed by the etching process, and the conductor pattern is formed, whereby a desired printed wiring board can be manufactured. The etching method is appropriately selected according to the conductor layer to be removed. For example, the above-mentioned etching solution can be applied.

  The method for manufacturing a printed wiring board according to an embodiment of the present disclosure can be applied not only to manufacturing a single-layer printed wiring board but also to a multilayer printed wiring board, and also to manufacturing a printed wiring board or the like having a small diameter through hole. Applicable.

  The photosensitive resin composition of this embodiment can be suitably used for manufacturing a wiring board. That is, one of the preferred embodiments of one embodiment of the present disclosure is (A) component: binder polymer, (B) component: photopolymerizable compound, and (C) component: 2,4,5-tria. A photopolymerization initiator containing at least one selected from the group consisting of a reel imidazole dimer and a derivative thereof, and a (D) component: a nitroxyl compound, wherein the (D) component is 2, 2, It is an application of a photosensitive resin composition containing a compound having a 6,6-tetramethylpiperidine-1-oxyl structure to the production of a printed wiring board.

  A more preferred embodiment is the application of the above-mentioned photosensitive resin composition to the production of a high-density package substrate, and the application of the above-mentioned photosensitive resin composition to the semi-additive construction method. Hereinafter, an example of a manufacturing process of a wiring board by the semi-additive method will be described with reference to the drawings.

  In FIG. 2A, a substrate (circuit forming substrate) in which the conductor layer 10 is formed on the insulating layer 15 is prepared. The conductor layer 10 is, for example, a metallic copper layer. In FIG. 2B, the photosensitive resin composition layer 32 is formed on the conductor layer 10 of the substrate by the photosensitive layer forming step. In FIG. 2C, the mask 20 is placed on the photosensitive resin composition layer 32, and the actinic ray 50 is applied to the photosensitive resin composition layer 32 by the above-mentioned exposure step, and the region where the mask 20 is placed. A region other than the above is exposed to form a photo-cured portion on the photosensitive resin composition layer 32. In FIG. 2D, in the photosensitive resin composition layer 32, a region other than the photo-cured portion is removed from the substrate by a developing process to form a resist pattern 30 which is the photo-cured portion on the substrate. In FIG. 2E, a plating layer 42 is formed on the conductor layer 10 by a plating process using the resist pattern 30 which is a photo-cured portion as a mask. In FIG. 2F, after the resist pattern 30 which is the photo-cured portion is peeled off with a strong alkaline aqueous solution, a part of the plating layer 42 and the conductor layer 10 masked by the resist pattern 30 are flash-etched. The conductor pattern 40 is formed by removing. The material of the conductor layer 10 and the plating layer 42 may be the same or different. Although the method of forming the resist pattern 30 using the mask 20 has been described with reference to FIG. 2, the resist pattern 30 may be formed by a direct drawing exposure method without using the mask 20.

  Hereinafter, one embodiment of the present disclosure will be described more specifically with reference to examples. However, the embodiments of the present disclosure are not limited to the following examples.

(Examples 1 to 11 and Comparative Examples 1 to 7)
(Preparation of solution of photosensitive resin composition)
Example 1 was prepared by mixing the components (A) to (G) and the component (O) shown in Tables 2 to 4 with 9 g of acetone, 5 g of toluene and 5 g of methanol at the blending amounts (g units) shown in the same table. To 11 and solutions of the photosensitive resin compositions of Comparative Examples 1 to 7 were prepared. The blending amount of the component (A) shown in Tables 2 to 4 is the mass (solid content) of the nonvolatile content. Details of each component shown in Tables 2 to 4 are as follows. In addition, "-" means unblended.

Component (A): Binder polymer [Synthesis of binder polymer (A-1)]
90 g of methacrylic acid which is a polymerizable monomer (monomer), 6 g of methyl methacrylate, 150 g of styrene and 54 g of benzyl methacrylate (mass ratio 30/2/50/18) and 1.5 g of azobisisobutyronitrile. The solution obtained by mixing was designated as "solution a".

  A solution obtained by dissolving 0.5 g of azobisisobutyronitrile in 100 g of a mixed solution (mass ratio 3: 2) of 60 g of methyl cellosolve and 40 g of toluene was designated as "solution b".

  A flask equipped with a stirrer, a reflux condenser, a thermometer, a dropping funnel and a nitrogen gas introducing tube was charged with 300 g of a mixed liquid (mass ratio 3: 2) of 180 g of methyl cellosolve and 120 g of toluene, and nitrogen gas was introduced into the flask. The mixture was heated with stirring while being blown, and the temperature was raised to 80 ° C.

  The solution a was added dropwise to the mixed solution in the flask over a period of 4 hours at a constant dropping rate, and then stirred at 80 ° C. for 2 hours. Then, the above solution b was added dropwise to the solution in the flask over a period of 10 minutes at a constant dropping rate, and then the solution in the flask was stirred at 80 ° C. for 3 hours. Furthermore, the solution in the flask was heated to 90 ° C. while stirring for 30 minutes, stirred at 90 ° C. for 2 hours, then cooled to room temperature to stop stirring, and a solution of the binder polymer (A-1) was prepared. Obtained. The room temperature referred to in this specification means 25 ° C.

  The nonvolatile content (solid content) of the binder polymer (A-1) was 47.4 mass%, the weight average molecular weight was 44000, the acid value was 196 mgKOH / g, and the dispersity was 1.6.

  The weight average molecular weight (Mw) was derived by measuring it by gel permeation chromatography (GPC) and converting it using a calibration curve of standard polystyrene. The conditions of GPC are shown below.

[GPC conditions]
Pump: Hitachi L-6000 type (Hitachi, Ltd.)
Column: 3 in total, column specifications: 10.7 mmφ x 300 mm
Gelpack GL-R440
Gelpack GL-R450
Gelpack GL-R400M (above, Hitachi Chemical Co., Ltd.)
Eluent: Tetrahydrofuran (THF)
Sample concentration: NV (nonvolatile component concentration) 120 mg of a binder polymer solution of 47.4 mass% was sampled and dissolved in 5 mL of THF to prepare a sample.
Measurement temperature: 40 ° C
Injection volume: 200 μL
Pressure: 49 Kgf / cm ² (4.8 MPa)
Flow rate: 2.05 mL / min Detector: Hitachi L-3300 RI (Hitachi, Ltd.)

[Synthesis of Binder Polymers (A-2) and (A-3)]
As the polymerizable monomer (monomer), the binder polymer (A-2) was prepared in the same manner as in the solution of the binder polymer (A-1) except that the materials shown in Table 1 were used at the mass ratios shown in the same table. ), The solution of (A-3) was obtained. The nonvolatile content (solid content) of each of the binder polymers (A-2) and (A-3) was 47.4% by mass.

  With respect to the binder polymers (A-1) to (A-3), Table 1 shows the mass ratio (%) of the polymerizable monomer (monomer), the acid value, the weight average molecular weight, and the dispersity. In addition, "-" means unblended.

Component (B): B-1: 2,2-bis (4- (methacryloxydiethoxy) phenyl) propane (Hitachi Chemical Co., Ltd., “FA-324M”)
B-2: 2,2-bis (4- (methacryloxide dodecaethoxytetrapropoxy) phenyl) propane (ethylene oxide average 12 mol and propylene oxide average 4 mol adduct) (Hitachi Chemical Co., Ltd., "FA-3200MY")
B-3: polyoxyalkylene glycol dimethacrylate (Hitachi Chemical Co., Ltd., “FA-023M”, both (poly) oxyethylene group (average 6 mol) and (poly) oxypropylene group (average 12 mol) in the molecule. Compound having

Component (C) (2,4,5-triarylimidazole dimer and its derivative)
C-1: 2,2'-bis (2-chlorophenyl) -4,4 ', 5,5'-tetraphenylbiimidazole [2- (2-chlorophenyl) -4,5-diphenylimidazole dimer] (Hampford, "B-CIM")

(Photopolymerization initiator other than 2,4,5-triarylimidazole dimer and its derivative)
C'-2: Diphenyl-2,4,6-trimethylbenzoylphosphine oxide (BASF, "Lucirin TPO")

Component (D) D-1: 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxyl free radical (Tokyo Chemical Industry Co., Ltd.)
-D-2: 4-hydroxy-2,2,6,6-tetramethylpiperidine-1-oxylbenzoate free radical (Tokyo Chemical Industry Co., Ltd.)
D-3: 4-acetamido-2,2,6,6-tetramethylpiperidine-1-oxyl free radical (Tokyo Chemical Industry Co., Ltd.)

(E) component-E-1: 4-tert-butyl catechol (DIC Corporation, "DIC-TBC")

Component (F): F-1: 1-phenyl-3- (4-methoxystyryl) -5- (4-methoxyphenyl) pyrazoline (Nippon Kagaku Kogyo Co., Ltd.)
F-2: 2,4-diethylthioxanthone (Nippon Kayaku Co., Ltd., "DETX-S")
・ F-3: N-methylacridone (Tokyo Chemical Industry Co., Ltd.)

(G) component G-1: leuco crystal violet (Yamada Chemical Co., Ltd., "LCV")

Other ingredients (dye)
-O-1: Malachite Green (Osaka Organic Chemical Industry Co., Ltd., "MKG")

<Production of photosensitive element>
The solution of the photosensitive resin composition obtained above was applied onto a polyethylene terephthalate film (“FB-40”, Toray Industries, Inc., “FB-40”) having a thickness of 16 μm (support), and hot air at 70 ° C. and 110 ° C. A photosensitive resin composition layer having a film thickness after drying of 25 μm was formed by sequentially performing drying treatment with a convection dryer. A polypropylene film (Oji Paper Co., Ltd., "E-200K") (protective layer) was attached onto the photosensitive resin composition layer, and a support, a photosensitive resin composition layer, and a protective layer were laminated in this order. The obtained photosensitive elements were respectively obtained.

<Production of laminated substrate>
A copper-clad laminate (Hitachi Chemical Co., Ltd., "MCL-E-679F") (hereinafter referred to as "substrate") composed of a glass epoxy material and copper foils (thickness 16 μm) formed on both surfaces thereof. After heating to 80 ° C., the photosensitive elements according to Examples 1 to 11 and Comparative Examples 1 to 7 were laminated on the copper surface of the substrate. Lamination was carried out under conditions of a temperature of 120 ° C. and a laminating pressure of 4 kgf / cm ² (0.4 MPa) such that the photosensitive resin composition layer of each photosensitive element was in close contact with the copper surface of the substrate while removing the protective layer. Went below. Then, it was left to cool to 23 ° C. to obtain a laminated substrate in which the photosensitive resin composition layer and the support were laminated on the copper surface of the substrate.

<Evaluation of sensitivity>
On the support of the obtained laminated substrate, a concentration region of 0.00 to 2.00, a concentration step of 0.05, a tablet size of 20 mm x 187 mm, and a size of each step is 3 mm x 12 mm, a 41-step tablet. The photo tool having the above was stuck. Using a direct drawing exposure machine (“DE-1UH”, Hitachi Via Mechanics Co., Ltd.) using a blue-violet laser diode with a wavelength of 405 nm as a light source, the photosensitive resin composition layer was applied to the photosensitive resin composition layer through a photo tool and a support. Exposed.

After the exposure, the support was peeled off from the laminated substrate to expose the photosensitive resin composition layer, and the unexposed portion was removed by spraying a 1 mass% sodium carbonate aqueous solution at 30 ° C. for 60 seconds. In this way, a resist pattern made of a cured product of the photosensitive resin composition was formed on the copper surface of the substrate. The sensitivity of the photosensitive resin composition was evaluated by measuring the remaining step number (step step number) of the step tablet obtained as a resist pattern (cured film). The sensitivity is indicated by the amount of energy (unit: mJ / cm ² ) at which the number of steps is 14 steps, and the lower the value, the better the sensitivity. If this numerical value is 200 mJ / cm ² or less, it can be said that the film has sufficient sensitivity. The results are shown in Tables 5 to 7.

<Evaluation of resolution and adhesion>
Drawing in which the line width (L) / space width (S) (hereinafter referred to as “L / S”) is 3/3 to 30/30 (unit: μm) on the support of the obtained laminated substrate. The patterns (the drawing pattern for resolution evaluation and the drawing pattern for adhesion evaluation) were brought into close contact with each other. The resolution evaluation drawing pattern is a drawing pattern that forms a space (void) in the cured product of the photosensitive resin composition. Then, with respect to the photosensitive resin composition layer, the 41 steps of the step tablet was exposed to the same amount of energy as the remaining step number of 14 steps through the phototool, the drawing pattern and the support using the same direct drawing exposure machine as in the sensitivity evaluation. Exposure (drawing). After exposure, development processing similar to the evaluation of the above sensitivity was performed.

  After development, the space portion (unexposed portion) is removed, and the line portion (exposed portion) is formed without causing meandering and chipping, and the resolution is determined by the minimum value of the line width / space width in the resist pattern. (Resolution) and adhesion were evaluated. The resolution was evaluated by the minimum value of the space width, and the adhesion was evaluated by the minimum value of the line width. The smaller this value is, the better the resolution and the adhesion are. The results are shown in Tables 5 to 7.

<Registration evaluation>
By observing the line portion having a line width of 12 μm in the resist pattern formed in the above evaluation of resolution and adhesion, the resist skirt (resist skirt generation amount) was evaluated. Using a scanning electron microscope (SEM) (Hitachi High-Technologies Corporation, "SU-1500"), the resist shape was observed at an acceleration voltage of 15 kV, a magnification of 3,000 times, and a tilt angle of 60 degrees, and the following criteria were used. The resist skirt was evaluated with. That is, when the maximum value of the skirt length generated from the resist side surface and the resist bottom portion was 0 μm or more and less than 0.5 μm, it was evaluated as “A”, and when it was 0.5 μm or more, it was evaluated as “B”. When an undercut was observed on the bottom of the resist, it was evaluated as "C". The evaluation results are shown in Tables 5 to 7.

※１：ライン幅１２μｍのレジストパターンを形成できなかったため、評価不可。

* 1: Evaluation is not possible because a resist pattern with a line width of 12 μm could not be formed.

  As is clear from Tables 5 to 7, photopolymerization containing a binder polymer, a photopolymerizable compound, and at least one selected from the group consisting of 2,4,5-triarylimidazole dimers and their derivatives. Resist pattern formed using the photosensitive resin compositions of Examples 1 to 11 containing an initiator and a nitroxyl compound containing a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure Was excellent in sensitivity, resolution, adhesiveness and resist skirt reduction. On the other hand, in Comparative Examples 1 to 7, it was difficult to improve all of the sensitivity, the resolution, the adhesiveness and the resist skirt reduction property.

  The photosensitive resin composition according to one embodiment of the present disclosure is applied as a material for forming a resist pattern for manufacturing a printed wiring board. In particular, the above-mentioned photosensitive resin composition has good sensitivity, resolution, adhesion, and resist skirt reducing property, so that a printed wiring having high-density wiring such as high-density package substrate and silicon chip rewiring. It is also suitably used for forming a resist pattern for manufacturing a plate with high accuracy and efficiency.

  DESCRIPTION OF SYMBOLS 1 ... Photosensitive element, 2 ... Support, 3 ... Photosensitive resin composition layer, 4 ... Protective layer, 10 ... Conductor layer, 15 ... Insulating layer, 20 ... Mask, 30 ... Resist pattern, 32 ... Photosensitive resin composition Material layer, 40 ... Conductor pattern, 42 ... Plating layer.

Claims (8)

A method for manufacturing a printed wiring board, comprising a step of etching or plating a substrate on which a resist pattern is formed by a method of forming a resist pattern,
The method of forming the resist pattern,
On the substrate, a photosensitive resin composition, or a photosensitive layer forming step of forming a photosensitive resin composition layer using a photosensitive element,
An exposure step of irradiating at least a part of the region of the photosensitive resin composition layer with an actinic ray, and photo-curing the region to form a cured product region,
A developing step of removing a region other than the cured product region of the photosensitive resin composition layer from the substrate, and forming a resist pattern which is the cured product region on the substrate,
Have
The photosensitive resin composition,
(A) component: a binder polymer,
Component (B): a photopolymerizable compound,
Component (C): a photopolymerization initiator containing at least one member selected from the group consisting of 2,4,5-triarylimidazole dimers and derivatives thereof,
Component (D): a nitroxyl compound,
Contains
The component (D) contains a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure,
The photosensitive element is
A support, and a photosensitive resin composition layer formed using the photosensitive resin composition provided on the support,
A method for manufacturing a printed wiring board, comprising: A method for manufacturing a printed wiring board, comprising a step of etching or plating a substrate on which a resist pattern is formed by a method of forming a resist pattern ,
The method of forming the resist pattern,
On the substrate, a photosensitive resin composition, or a photosensitive layer forming step of forming a photosensitive resin composition layer using a photosensitive element,
An exposure step of irradiating at least a part of the region of the photosensitive resin composition layer with an actinic ray, and photo-curing the region to form a cured product region,
A developing step of removing a region other than the cured product region of the photosensitive resin composition layer from the substrate, and forming a resist pattern which is the cured product region on the substrate,
Have
The photosensitive resin composition,
(A) component: a binder polymer,
Component (B): a photopolymerizable compound,
Component (C): a photopolymerization initiator containing at least one member selected from the group consisting of 2,4,5-triarylimidazole dimers and derivatives thereof,
Component (D): a nitroxyl compound,
Contains
The component (A) has a structural unit derived from (meth) acrylic acid and a structural unit derived from a (meth) acrylic acid alkyl ester,
The content of the structural unit derived from the (meth) acrylic acid alkyl ester is 10% by mass or less based on the total mass of the structural units derived from the polymerizable monomer forming the binder polymer,
The component (D) contains a compound having a 2,2,6,6-tetramethylpiperidine-1-oxyl structure,
The photosensitive element is
A support, and a photosensitive resin composition layer formed using the photosensitive resin composition provided on the support,
A method for manufacturing a printed wiring board, comprising: The component (B) is an ethylenic compound in the molecule selected from the group consisting of bisphenol type di (meth) acrylate, hydrogenated bisphenol A type di (meth) acrylate and EO / PO modified polyalkylene glycol di (meth) acrylate. The production method according to claim 2 , comprising at least one compound having two saturated groups. The production method according to claim 2 or 3 , wherein the 2,4,5-triarylimidazole dimer and a derivative thereof include a compound represented by the following general formula (1).

[In the formula (1), Ar ¹ , Ar ² , Ar ³ and Ar ⁴ may be each independently substituted with at least one substituent selected from the group consisting of an alkyl group, an alkenyl group and an alkoxy group. Represents a good aryl group, X ¹ and X ² each independently represent a halogen atom, an alkyl group, an alkenyl group or an alkoxy group, and p and q each independently represent an integer of 1 to 5. However, when p is 2 or more, a plurality of X ¹ present may be the same or different, and when q is 2 or more, a plurality of X ² may be the same or different. ] Component (E): containing phenolic compounds further process according to any one of claims 2-4. The manufacturing method according to claim 5 , wherein the content of the component (E) is 0.0001 to 0.1 part by mass based on 100 parts by mass of the total amount of the component (A). Component (F): contains a sensitizer further comprising said component (F) is a pyrazoline compound, a manufacturing method according to any one of claims 2-6. The manufacturing method according to any one of claims 2 to 7 , wherein the wavelength of the actinic ray is in the range of 340 nm to 430 nm.

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